ObjectiveTo explore the application value and operation skills of arthroscopic automatic reverse guide wire passer (hereinafter referred to as wire passer) in the posterior meniscus root reconstruction. Methods Between August 2015 and December 2020, 36 patients with posterior meniscus root tears were admitted. There were 16 males and 20 females, with an average age of 46 years (range, 26-66 years). There were 15 cases of sports injury and 21 cases of degenerative injury. The disease duration was 3-180 days, with a median of 28 days. The posterior root of the medial meniscus was injured in 29 cases, and the posterior root of the lateral meniscus was injured in 7 cases. The preoperative Lysholm score of the knee joint was 47.6±3.9, and the International Knee Score Committee (IKDC) score was 39.3±3.0. The meniscus was sutured by using wire passer under arthroscopy. During operation, the suture operation was evaluated according to the self-defined evaluation standard. Lysholm score and IKDC score were used to evaluate knee joint function. Results All meniscuses were sutured successfully by using wire passer. The operation time of suture was 5-15 minutes, with an average of 10 minutes. According to the self-defined evaluation standard, the suture operation was scored as 0-10, with an average of 5. After operation, except for 2 cases of incision fat liquefaction, the incisions of the other patients healed by first intention. All patients were followed up 1-3 years, with an average of 1.5 years. The Lysholm score was 88.2±2.1 and the IKDC score was 51.7±2.3 at 1 year after operation, showing significant difference when compared with preoperative ones (P<0.001). Fifteen cases underwent MRI re-examination, the results showed that the continuity and integrity of the posterior root had been restored. Conclusion Under arthroscopy, the wire passer for the posterior meniscus root reconstruction has the advantages of simple operation, reliable suture quality, and shorter operation time.
Objective The bone marrow mesenchymal stem cells (BMSCs) have the capacity to differentiate into insul in-producing cells (IPCs) in vitro. However, low differentiation efficiency and poor maturity are the main obstacles. To investigate the feasibil ity of BMSCs differentiation into IPCs in diabetic pancreatic microenvironment of pigs. Methods BMSCs were isolated and purified from the bone marrow of a 4-week-old male pig. Fifteen female pigs (aged 8 to 10 weeks, weighing 8 to 10 kg) were randomly divided into 3 groups: normal control group (group A, n=5), diabetic control group (group B, n=5), and BMSCs transplanted group (group C, n=5). The pigs of groups B and C were treated by auris vein injections of styeptozocin and alloxan for 3 days to induce diabetes mell itus (DM) model, whose blood glucose level 2 days all greater than 17 mmol/L was successful DM model. A total of 1.1 mL of the 3rd passage BMSCs labeled with enhanced green fluorescent protein (EGFP), with cell density of 5 × 107/ mL, were injected into subcapsular pancreas of group C at multi ple points, normal saline at the same dosage into those of groups A and B. After 30 days of monitoring blood glucose, the histological analysis of islet number and size were done; the immunofluorescence staining was used to detect the protein expression of insul in in the new-formed islets. The EGFP+ cells were collected from the sections using laser-capture microdissection; RT-PCR was used to detect insulin mRNA and pancreatic and duodenal homeobox factor 1 (PDX1) mRNA expressions from EGFP+ cells, and the insul in and sexdetermining region of the Y chromosome (SRY) genes were detected by fluorescence in situ hybridization (FISH). Results The blood glucose level decreased significantly in group C when compared with that in group B from 18 days and gradually decreased with time (P lt; 0.05). The histological observation showed that the number of islets was increased significantly in group C when compared with that in group B (10.9 ± 2.2 vs. 4.6 ± 1.4, P lt; 0.05), and there was no significant difference when compared with that in group A (10.9 ± 2.2 vs.12.6 ± 2.6, P gt; 0.05). The size of new-formed islets in group C was significantly smaller than that in group A [(47.2 ± 19.6) μm vs. (119.6 ± 27.7) μm, P lt; 0.05]. The immunofluorescence staining showed that new-formed islets of group C expressed insulin protein. RT-PCR showed that the microdissected EGFP+ cells of group C expressed insulin mRNA and PDX-1 mRNA. FISH showed that the new-formed islet cells of group C contained SRY gene in Y chromosome and insulin double positive cells. Conclusion BMSCs can differentiate into IPCs in diabetic pancreatic microenvironment of pigs.
ObjectiveTo investigate the effects and mechanisms of differentiation of bone marrow mesenchymal stem cells (BMSCs) into insulin producing cells (IPCs) induced by injured pancreatic tissue extract of rat. MethodsEighty 6-week-old Sprague Dawley rats were selected. Forty rats underwent removal of 60% pancreas and the injured pancreas tissue was obtained after 48 hours to prepare the injured pancreatic tissue extract; and normal pancreatic tissue extract was prepared from the other 40 rats. The BMSCs were isolated from the tibia and femur of 4-week-old Sprague Dawley rats. BMSCs at passage 3 were co-cultured with rat injured pancreatic tissue extract as experimental group, with rat normal pancreatic tissue extract as normal control group, and with cell culture medium as blank control group for 14 days. The expressions of pancreas development related genes and proteins were detected, and cell morphological changes were observed. Then the C peptide positive cell rate was detected by flow cytometry analysis and insulin secretion levels were detected by glucose stimulation experiment at 14 days. ResultsInjured pancreatic tissue extract can induced BMSCs differentiating into IPCs. The pancreatic development related genes of pancreatic duodenal homeobox 1 (PDX-1), islet 1, Nkx6.1, glucose transporter type 2, proprotein convertase 2, neurogenin 3, and somatostatin were expressed sequentially in the differentiation process of experimental group; mature pancreatic proteins of PDX-1, insulin, C peptide, Nkx6.1 also were expressed. But there was no morphological changes and expression of pancreatic development related genes and proteins in normal control and blank control groups. The C peptide positive cell rate of experimental group (13.8%±1.8%) were significantly higher than those of normal control and blank control groups (1.6%±0.4%) (P<0.05). The insulin secretion of experimental group was significantly higher than that of normal control and blank control groups (P<0.05), but it was 1/40 and 1/47 of natural islet cells (P<0.05). ConclusionAfter pancreatic injury, injured pancreas would secrete transcription proteins related to development, differentiation, and repair of pancreas, which can promote the differentiation of BMSCs into IPCs.